Tangential Force to pull a cylindrical plastic cover

[vaas44]

I would like to know views on the force required to pull a cylindrical cover.

A plastic shade cover is almost 290 ft in length and 150 ft in breadth. It is wrapped around a cylindrical wooden rod which is at a height of 7 ft from the ground. The cover is pulled by plastic ropes to the right to its complete length of 290 ft. Consider the thickness of plastic cover to be 10 mm and density of plastic as 850 kg/m3. The ropes are pulled by 7 people towards right.

How much force is required to pull the cover completely to the right?

Should the force be equal on all the ropes?

Please give views on an efficient pulley system to help the 7 people.

 

[Valerie Park]

To answer your first question, the force required to pull the cover completely to the right would depend on the friction generated between the ground and the plastic shade cover. If the surface is slippery, then less force would be needed. If the surface is rough, then more force would be needed. It would also depend on the strength of the plastic ropes used to pull the cover. The stronger the ropes, the less force would be needed to pull the cover all the way to the right. As for the second question, it would be more efficient if the force applied on the ropes was not equal. This is because if the force is divided equally among the 7 people, there will be some rope sections that are pulled more and some that are pulled less. For example, the section of rope closest to the wooden rod will be pulled slightly more than the sections farther away. To achieve a more efficient result, each person should pull with a different force depending on their position relative to the wooden rod. In terms of an efficient pulley system, it would help distribute the force more evenly among the 7 people. It would also reduce the amount of force required to pull the cover all the way to the right. You could use a simple pulley system with two or more pulleys attached to the rope, which would allow the force to be distributed in a more efficient manner.